Re: SRS for skin cancer

[Chris Alston <alstonc@odrge.odr.georgetown.edu>]

>  This press release got a round of laughs in our dept this morning, but if it
>>works, I guess we have to take it seriously.  How about SRS for mole or
>>wrinkle removal?  This could start an entirely new field of cosmetic
>>radiosurgery.  - Carter Schroy
>>
>>LEXINGTON, Mass., July 30 /PRNewswire/ -- Photoelectron Corporation (Nasdaq:
>>PECX), developer of the Photon Radiosurgery System (PRS), a proprietary x-ray
>>delivery system for tumor therapy, announced today the commencement of skin
>>tumor trials at Our Lady of Mercy Medical Center, a University Hospital of New
>>York Medical College in New York.
>
>There are probably a few details that would help people to understand this.
>I have worked with this company in the past to help in the characterization
>of their rather novel device and to support a clinical trial of brain met
>treatment.
>
>The device used is essentially a hand held xray "needle" operating at 50
>KVp, which produces a nearly spherical dose distribution falling off like
>1/r^3 with a dose rate of about 2 Gy/min at 1 cm from the tip (in tissue).
>The "needle" is actually a 10 cm long, 3 mm diameter hollow Beryllium tube,
>down which electrons are fired to a gold target at the end. For the skin
>treatments the company has developed a set of cones that fit over the end
>of the needle and result in a fairly uniform dose over a reasonable
>diameter (maybe a few cm) at the base of the cone. The neat thing about the
>equipment is that it is 9 Volt battery operated and fits into a couple of
>suitcase sized cases when not in use. And it can be operated in a room
>without special shielding.
>
>The reason the device is called the Photon Radiosurgery System (PRS) is
>that it was originally used to treat brain metastases stereotactically by
>mounting it on a stereotactic head frame. Initial results of clinical
>trials for treating brain metastases were encouraging, but applicability
>was somewhat limited and competition for SRS treatment of brain mets is
>fierce. So the folks at the company have been looking for other
>applications of a low energy xray source. Clearly facial basal or squamous
>skin lesions looked feasible.
>
>For those interested to look further into it see:
>
>
>Dinsmore M, Yanch JC, Sliski AP, Harte KJ:  "New X-ray Generator for
>Interstitial Radiotherapy".  Transactions of American Nuclear Society,
>Vol. 70, pp. 24-25, 1994.
>
>Cosgrove R, Zervas NT, Valensuela R, Biggs P, Hochberg FH, Pardo F, Gall
>KP, Beatty J, Interstitial Photon Radiosurgery for Intracranial Tumors,
>Proceedings of the 2nd Congress of the International Stereotactic
>Radiosurgery Society, Boston, MA, (1995).
>
>Dinsmore M, Harte KJ, Sliski AP, Smith DO, Monikos PM, Dalterio MJ, Boom
>AJ, Leonard WF, Oettinger PE, Yanch JC "A New Miniature X-ray Source for
>Interstitial Radiosurgery:  Device Description".  Med Phys , 1996, 23, (1),
>45-52.
>
>Beatty J, Biggs PJ, Gall KP, Okunieff P, Pardo FS, Harte KJ, Dalterio MJ,
>Sliski AP, A New Miniature X-Ray Device for Interstitial Radiosurgery:
>Dosimetry, Med. Phys., 1996, 23 (1) 53-62.
>
>Douglas RM, Beatty J, Gall KP, Valenzuela RF, Biggs P,  Okunieff P, Pardo
>FS, Dosimetric Results from a Feasibility Study of a Novel Radiosurgical
>Source for
>Irradiation of Intracranial Metastases, Int. J. Radiation Oncology Biol.
>Phys., 1996, 36(2), 443-450.
>
>Hakim R, Zervas NT, Hakim F, Butler WE, Beatty J, Yanch JC, Biggs PJ, Gall
>KP, Sliski AP, Initial Characterization of the Dosimetry and Radiobiology
>of a Device for Administering Interstitial Stereotactic Radiosurgery,
>Neurosurgery, 1997, 40 (3) 510-517.
>
>T. Yasuda, Beatty J, Biggs PJ, Gall KP, Two Dimensional Dose Distribution
>of a Miniature X-Ray Device for Stereotactic Radiosurgery, Med. Phys.,
>1998, 25 (7) 1212-1216.
>
>
>
>Kenneth P. Gall, PhD.
>Director, Division of Physics and Dosimetry
>Department of Radiation Oncology
>University of Texas Southwestern Medical Center
>5323 Harry Hines Blvd.
>Dallas, Texas 75235-9122
>
>Gall@simmons.swmed.edu
>Phone (214) 648-7155
>Fax   (214) 648-7656
>
>                    *****
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>
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>
Chris Alston
alstonc@odrge.odr.georgetown.edu
I am not here a representative of my employer.

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